Originally Posted by Olaf Barthel
I has been possible since 1998 for the Amiga V40 operating system (Kickstart and Workbench) to compile itself on an Amiga.
After the build has finished, you can literally copy the disk images to floppy disks and install a blank hard drive using them (well, just creating a blank partition suits the same purpose). Don't forget to copy the AmigaOS source code to that blank partition, while you're at it.
You can then load the Kickstart ROM image appropriate for your machine, reboot it and boot from the recently installed natively-compiled Workbench. You can now restart the AmigaOS build again from scratch.
Some small portions are, however, not built natively. These concern printer drivers, aux-handler, mathieeedoubtrans.library and mathieeesingtrans.library. These require a cross-compiler (aux-handler is written in BCPL and needs the BCPL compiler, the math libraries need the math runtime library of the Green Hills 'C' compiler) or are so old that porting them to a modern compiler makes little sense (Alphacom, Diablo 630, Howtek Pixelmaster, Seiko 5300, Sharp JX-730, Tektronix 4693d, Toshiba P351SX, Xerox 4020, etc.). Replacements for aux-handler and the math libraries exist, and in this case work better than the originals
Even with these small omissions, it has been possible for some 18 years for the Amiga operating system to fully build itself on an Amiga. Well, that was mostly my
Amiga 3000UX with a 50 MHz 68060 CPU, but you get the general idea
okay.it sounds fine but still rather complicated. im all for building system natively, still i have doubts of advantage of it if it takes hundred times longer than cross compiling. i wouldnt insist on it no matter what.
actually to illustrate my workflow with aros 68k in comparison, i build or rebuild the whole os or desired module, like particular library or executable under linux crosscompiler after modification. using vmaretools feature i can simply copy the files in an instant over into a directory declared a winuae masstorage media and boot from there. when staisfied testing there i can attach an sd card or another masstorage media via usb to winuae and copy the data on that media, that i can use then to boot an actual amiga. to test the kickstart even there, you have to softkick it of course. none in their right mind would burn an eprom every time there is something to new test. i must admit i have not booted from a floppy since a while, but this is an option as well, since floppy images are being built alongside if you choose so.
this as example, i think it might be beneficial to organize build process of amiga-os in a similar manner, if a bigger team was expected to be involved. if you simply build it only yourself, or with one ot two collegues who are building only specific parts and know since years how to do it, then there is no problem of course. but admittedly licensing is what is a major issue, here, not the logistics.